DISEASE: Aster yellows
HOST: Marigold
Infected plant (left) with yellowing and stunting.
Aster yellows | Marigold
DISEASE: Aster yellows
HOST: Marigold (Tagetes erecta)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: M. Shurtleff
DISEASE: Blister spot
HOST: Apple
Late stage of blister spot. The purplish black lesions are associated with lenticels and stomata.
Blister spot | Apple
DISEASE: Blister spot
HOST: Apple (Malus domestica 'Crispin')
PATHOGEN: Pseudomonas syringae pv. papulans
SOURCE: T. Burr
DISEASE: Greening disease
HOST: Periwinkle
Diseased plants with phyllody and greenish yellow leaves.
Greening disease | Periwinkle
DISEASE: Greening disease
HOST: Periwinkle (Vinca minor)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: E. Braun
DISEASE: Pseudomonas leaf spot
HOST: Marigold
Marigolds with yellow apical chlorosis attributed to toxin production by the pathogen.
Pseudomonas leaf spot | Marigold
DISEASE: Pseudomonas leaf spot
HOST: Marigold (Tagetes erecta)
PATHOGEN: Pseudomonas syringae pv. tagetis
SOURCE: R. Durbin
DISEASE: Pseudomonas leaf spot
HOST: Marigold
Chlorotic leaves with total loss of chlorophyll. Disease is also known as toxic chlorosis.
Pseudomonas leaf spot | Marigold
DISEASE: Pseudomonas leaf spot
HOST: Marigold (Tagetes erecta)
PATHOGEN: Pseudomonas syringae pv. tagetis
SOURCE: R. Durbin